This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A015666 #11 Oct 23 2018 06:52:26
%S A015666 1,5,15,15,105,1845,5175,-11025,363825,4011525,46734975,367203375,
%T A015666 -909822375,105415435125,1137191430375,-7081746296625,202916199110625,
%U A015666 6031044627733125,96887972385579375,589023558627879375
%N A015666 Expansion of e.g.f. theta_3^(5/2).
%D A015666 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 102.
%H A015666 Seiichi Manyama, <a href="/A015666/b015666.txt">Table of n, a(n) for n = 0..449</a>
%t A015666 nmax = 25; CoefficientList[Series[EllipticTheta[3, 0, x]^(5/2), {x, 0, nmax}], x] * Range[0, nmax]! (* _Vaclav Kotesovec_, Oct 23 2018 *)
%K A015666 sign
%O A015666 0,2
%A A015666 _N. J. A. Sloane_